The present invention concerns a locking mechanism for a door driven by a motorized transmission, especially an overhead door, a tilting, swinging, or sectional door for instance, whereby the locking mechanism operates in conjunction with a coupling mechanism that couples the door""s panel to a carrier, the transmission moves the carrier back and forth, preventing the closed door from opening when not subjected to force by the carrier, the locking mechanism includes a lever and a connector, the lever is mounted directly or indirectly on the carrier and pivots around a first axis in two opposite directions, the lever is provided with an engagement mechanism that engages a stationary counterbearing, the counterbearing operates in conjunction with a track that guides the carrier, locking the door, the engagement mechanism engages the counterbearing as the lever pivots in one direction and disengages it as the lever pivots in the opposite direction, the connector is rigid and is preferably in the form of a connecting rod, the connecting rod has an attachment mechanism at one end that attaches it to the door panel and is pivoted at the other end to the lever around another axis that is some distance from the first axis, whereby the lever accordingly pivots around the firstaxis in the first direction when the connector is pushed while in alignment with the door and in the opposite direction when the connector is pulled while in alignment with the door. The present invention also concerns a door-drive mechanism provided with such a locking mechanism. A locking mechanism and door-drive mechanism of this genus is known from European Patent 0 743 416 A1, which will be discussed in detail hereinafter.
Motorized drive mechanisms that open and close overhead doors have long been known.
A mechanism of this genus is known from DE 2 741 539 A1 for example. They usually include a carrier, preferably a carriage, that can be moved along the track positioned horizontal above the route traveled by the door. The carrier is usually attached to the door by connecting rods. Detaching the carrier from the door or from a traction mechanism between the carrier and the drive mechanism in the event of an emergency, when the mechanism malfunctions, has also long been known.
Problems can be encountered with such drive mechanisms. The closed door can be forced up from outside by muscle power, the carrier moving in the door-opening direction without or even against the force exerted by the transmission.
Additionally preventing the carriage and/or the closed door from unauthorized opening has accordingly often been proposed. Examples of such locking mechanisms are known from German Patent 1 961 916, U.S. Pat. No. 3,704,548, German 8 802 127 U1, French A 2 349 014, U.S. Pat No. 3,909,980, and the aforesaid European Patent 0 743 416 A1.
In German Patent 1 961 916, a carrier in the form of a carriage travels back and forth along a track between two stops. The closure stop is provided with a stationary pawl. The carriage is secured in its locking position when it engages the pawl. The engaged pawl is subject to tension. To disengage the carriage, it is attached by way of a two-armed lever to a traction mechanism between it and the motorized transmission. The lever""s arms act as stops, limiting its pivoting motion. The free end of one arm engages below the pawl when the lever is in its locking position. When the traction mechanism is actuated, the lever pivots before the carrier begins moving. The pawl is accordingly lifted and disengaged, releasing the carrier. This drive mechanism is indeed provided with a coupling mechanism that couples a carrier in the form of a carriage to the door, but the coupling mechanism pivots around the same axis as the lever, although independently thereof.
In the mechanism disclosed in U.S. Pat. No. 3,704,548, it is the upper end of the door and not the carrier in the form of a carriage that is locked. Releasing the tensioned locking device again in order to open the door requires a highly complicated system of levers and slides.
German 8 802 127 U1 discloses a locking mechanism wherein a connecting rod attached to the door lifts a carrier when force is applied to the door from outside and accordingly engages the carrier with a cogged rack or with a chain above it. This locking mechanism is not completely reliable. The carrier can move at a right angle to its intended direction, resulting in unpleasant rattling and imprecise movement. The carrier can even tilt out of alignment and impinge on the rack or chain in ordinary operation.
French A 2 349 014 discloses a locking mechanism wherein the connecting rod that comprises the coupling mechanism travels back and forth in a slot in the carrier. A pawl on the connecting rod pivots around a pin accommodated in the slot and engages a counterbearing on the track. As the carrier leaves its locking position, the connecting rod is pulled along the slot, disengaging the pawl by way of a sloping plane. The mechanism known from U.S. Pat. No. 3,909,980 also employs means of displacement comprising a pawl in conjunction with a slot and a sloping plane to lever the pawl out of its engagement against a counterbearing. Generally, devices of this genus, which exploit displacement of a rod in relation to a carrier, are problematic with respect to wear and are complicated to manufacture and to install and adjust on site.
The locking mechanism of the aforesaid genus known from European Patent 0 743 416 A1 on the other hand has proven very reliable and easy to manufacture and install. The connecting rod employed therein between the carrier and the door is not directly attached to the carrier but to a lever that pivots around an axis on the carrier. A coupling mechanism constituting a toggle composed of the rigid connector, which is in the form of a connecting rod, and the lever, couples the carrier to the door. The lever has only one arm and is provided with a hooked pawl in the vicinity of another pivoting axis and engaging a notch in the vicinity of the track. This mechanism has few moving parts, and they only pivot among themselves and are not relatively displaced. The mechanism is accordingly very simple and operates reliably in that, with the exception of the pawl, none of the components slide along any of the others, which would subject them to wear. The mechanism is also very easy to install and adjust.
Even this known mechanism, however, needs improvement with respect to its adaptability to various installation situations. The toggle for instance allows the connecting rod to rotate only to a limited extent without detriment to the function of the pawling system. This is of disadvantage in particular when the track is to be mounted high above the doorway. The site might also provide insufficient vertical space, in the opening and closing direction, that is, in which event a shorter connecting rod would be desirable. The limits dictated by the operation of the toggle will still be too narrow in some situations.
The object of the present invention is an improved locking mechanism and associated drive mechanism of the genus disclosed in European Patent 0 743 416 A1 that will operate just as reliably and that can be manufactured, installed, and adjusted just as easily while adapting readily to a wider range of situations on site.
This object is attained in accordance with the present invention in a locking mechanism of the aforesaid genus in that the lever comprises two arms, the connector being attached to the arm, and in that the mechanism that engages the counterbearing while or after the lever and hence the second arm pivots in the first direction, pushing the connector attached to the door, and that disengages the counterbearing while or after the lever and hence the second arm pivots in the opposite direction, pulling the connector attached to the door, is mounted on the second lever arm.
These amazingly simple measures allow the connector or connecting rod to be farther uncoupled from the lever. The connector, specifically the connecting rod, that is, can be attached to the door at a wider range of angles, while the lever is rotated in the first direction only when subjected to force in the opening direction.
A door-drive mechanism with a locking mechanism of this species can accordingly be installed considerably above the doorway and be provided with shorter connecting rods.
Advantageous embodiments of the present invention are addressed by the subsidiary claims.
Various types of engagement mechanism can be employed. The mechanism can for example be a pin that engages a barbed structure from a depression therein. In a simpler and preferred embodiment, however, the end of the second lever arm pointing along the first pivoting direction is provided with an engagement mechanism in the form of a hook or nose that hooks onto or engages behind the counterbearing while or after the lever pivots in the first direction and releases it while or after the lever pivots in the second direction.
To facilitate directly transmitting the pushing and pulling forces from the carrier to the door by way of the coupling mechanism, the lever and connecting rod, that is, during normal operation, one advantageous embodiment of the locking mechanism in accordance with the present invention features two stops, the first stop limiting the motion of the lever as it pivots in the first direction once engagement has been achieved and the second stop limiting the motion of the lever""s first and/or second arm as it pivots in the second direction once engagement has been achieved. The lever can accordingly pivot only to a limited extent, just far enough to engage or disengage.
The regulations that govern the safe operation of doors driven by motorized drive mechanisms prescribe that the doors can be opened in emergencies and when their drive mechanisms malfunction. This demand is of particular importance when the door is the only form of access to the other side. For such events, one particularly advantageous embodiment of the drive mechanism in accordance with the present invention features an emergency unbarring mechanism that disengages the lever, allowing the door to be opened by muscle power. The locking mechanism can accordingly be released when the drive mechanism malfunctions, in the event of a power failure for example, and the drive mechanism will not stand in the way of opening the door by muscle power. Since many door-drive mechanisms are self-inhibiting, however, it is not only the locking mechanism itself that must be overcome when opening the door by muscle power, but the motorized transmission itself. It will accordingly be of advantage for the emergency unbarring mechanism that unlocks the locking mechanism and uncouples the door to be constituted by the motorized transmission itself. It will be of further advantage in this case for the emergency unbarring mechanism to be provided for this purpose with a separating mechanism that separates the carrier from the motorized transmission. The separating mechanism in one preferred embodiment can be provided with an unlocking-lever component that manually shifts the carrier out of a normal position, wherein the carrier is coupled to the motorized transmission, and into a detachment position, wherein the carrier is detached from the motorized transmission, especially by traction means. The separating mechanism can for example be actuated by way of manually actuated traction means. The traction means can for example comprise a traction cord accessible from inside the door and/or a Bowden cord accessible from outside. Other meansxe2x80x94levers, rods, etc. for examplexe2x80x94of actuating the emergency unbarring mechanism are of course also conceivable. Although manual actuation is preferred, automatic actuation by way of an emergency mechanism of some sort is also possible.
To ensure that the locking mechanism can be unlocked to allow the door to be opened by muscle power, the emergency unbarring mechanism in one embodiment of the present invention can include means of applying tension, especially in the form of a spring that maintains the lever in its release position. The engaging component in all known locking mechanisms is maintained in its engaged position subject to tension. Although this feature does ensure that the engagement mechanism will engage and remain engaged as long as the door remains closed, it is not absolutely necessary in that the engagement mechanism must only remain engaged while the door is actually subjected to force from outside. If, for example, as provided in this particular embodiment of the present invention, the lever is maintained in its release position by tension, the advantage will be that the door can easily be opened by muscle power with the carrier coupled by way of the traction mechanism without having to first shift the engaging mechanism out of its engaged position. All that would be necessary to disengage the system in an emergency in such an embodiment would be to uncouple the carrier from the motorized transmission.
Practice has demonstrated, however, that this theoretically simplest approach is not sufficient in all cases to ensure absolutely reliable emergency unbarring. The emergency unbarring mechanism in one preferred embodiment of the present invention can accordingly include an unlocking mechanism that will when actuated shift and in particular force the lever out of its engaged position or locking position, whereupon the door panel can be pulled or pushed up, allowing the door to be opened subject to muscle power in an emergency.
The unlocking mechanism is also preferably designed such that, when the emergency unlatching mechanism is actuated, by tugging on the traction means for example, it will not pivot the second lever arm out of its engagement position and into its release position until the separating mechanism has separated the carrier. The emergency unbarring mechanism can accordingly be operated in two phases. In the first, the carrier is uncoupled from the motorized transmission. In the next phase, as the emergency unbarring mechanism continues to be actuated, by continuous tugging on the traction means for example, the locking mechanism will be unlocked. The unlocking mechanism that unlocks the locking mechanism in one concrete and advantageous embodiment is mounted on, located on, or associated with the unlocking-lever component that unlocks the carrier from the motorized transmission such that it will not, as the unlocking-lever component pivots out of its normal position and beyond its unlocking position, seize a vicinity of the lever that pivots along with the second lever arm such that the second lever arm will pivot in the second direction, until the unlocking-lever component has traveled beyond its unlocking position. In the simplest version of this embodiment, both the unlocking mechanism and the unlocking-lever component comprise a single component, that will, as it pivots out of its normal position around an acute angle, uncouple the carrier from the motorized transmission and, as it continues beyond that angle, seize the locking mechanism""s lever and force it out of its engagement position. In the simplest version, the unlocking mechanism is constituted by the unlocking-lever component itself, whereby once it has traveled beyond its unlocking position, the unlocking-lever component will directly seize the lever and push or pull it out of its engagement position. The unlocking-lever component in one preferred embodiment can be pivoted manually, especially by way of the traction means. The unlocking-lever component is connected to a coupling pin. The pin is in particular tensioned in the coupling position and couples the carrier to the traction mechanism. As it pivots into the unlocking position, the unlocking-lever component releases the pin. The unlocking-lever component is preferably provided with a contact vicinity that contacts a matching contact area on the lever, pivoting the second lever arm out of its engagement position and into its release position.
The contact area of the lever that constitutes the locking lever in another preferred embodiment is provided with a third lever arm that is connected to and pivots along with the second lever arm around the first axis. The third lever arm extends into the vicinity wherein the unlocking-lever component pivots such that, when the lever is in its engagement position and the unlocking-lever component in its normal position, the third arm will be far enough from one arm of the unlocking-lever component to allow emergency unbolting to take place in two phases. It is in this event preferable for the distance to be long enough to prevent the unlocking-lever component and the third lever arm from seizing each other until the unlocking-lever component has pivoted out of its normal position and beyond its unlocking position such that the second arm of the lever can be released as the unlocking-lever component continues pivoting.
One concrete embodiment of the present invention features a bearing that accommodates the lever, whereby the bearing extends downward from the carrier when the mechanism is employed as intended, the carrier travels back and forth along a track, the track extends horizontally above the route traveled by the door panel as the door opens, the first axis is provided against the bearing extending downward as viewed from a specified angle and at a distance from the horizontal track when the mechanism is employed as intended, and the first and/or the second axis are preferably provided on the bearing. This situation can be attained for example if the bearing is provided with a housing in the form of a sleeve or is sleeve-like or cylindrical, with the lever coming to rest against the interior wall surface of the housing upstream and/or downstream and above and/or below the axis during the pivoting motion.
Instead of the bearing that establishes a position below the carrier track. The first axis can be accommodated inside the carrier itself. In this case, the lever will be accommodated inside the carrier. The interior wall surfaces of the housing that face the first lever arm will preferably act as the first and/or second stop. The second axis will, however, preferably be below the carrier track when the mechanism is employed as intended.
The first lever arm in one especially advantageous embodiment can extend for this purpose downward, essentially downward, that is, from the first axis in when the mechanism is employed as intended such that, as it pivots in the first direction, its free end will move in the opening direction traveled by the carrier. The lever arm need not point precisely downward but only essentially downward, extending across the direction traveled by the door panel and/or the carrier and accordingly transmitting the maximum of torque. Due to the force exerted on the connecting rod during the first attempt to open the door from outside, the first lever arm will pivot into the premisses being closed off.
The second lever arm can extend upward, essentially upward, that is, from the first axis for example when the mechanism is employed as intended such that, as the arm pivots in the first direction, its free end will move along with the engagement mechanism opposite the direction traveled by the carrier until it arrives in its engagement position. The first and second lever arm in one embodiment of the present invention can thereby extend essentially perpendicular to each other, more or less at 180xc2x0, at least in the vicinity of the first axis. This approach will simplify manufacture of the lever, which will act like a motion-reversing lever.
The lever arms in one advantageous embodiment either constitute a simple single component or are otherwise fastened together, pivoting as a whole in both directions.
The first and second lever arms in one alternative embodiment, however, can be separate components coupled together. They will then preferably be coupled together by way of a carrier mechanism such that the second lever arm will move along with the first lever arm only when pivoting in one particular direction. It is accordingly preferably subjected to tension such that both lever arms will engage each other by way of the carrier mechanism. When force is exerted against the second lever arm in opposition to the engagement provided by the carrier mechanism, however, the latter will pivot out of engagement with the first lever arm. It will in this case be preferable for both the first and second lever arm to pivot simultaneously as the carrier travels in the opening direction and to uncouple from each other, especially by pivoting relative to each other, as the carrier travels in the closing direction. The advantage here is that the second lever arm can slip beyond the counterbearing and snap into place without having to carry the first lever arm and the connector coupled thereto along with it. Furthermore, the second lever arm, once uncoupled from the first lever arm by the emergency release mechanism comprising the unlocking mechanism, can easily be shifted out of its engagement position without having to move the first lever arm and hence the coupling mechanism. With such an embodiment it is also conceivable in principle to eliminate two-phase actuation of the emergency unbolting mechanism or to unlock the locking mechanism first and then [un] couple the carrier from the motorized transmission. To ensure that the locking mechanism will remain locked in any case once the lever arms have been uncoupled, it will be preferable for the second lever arm to be tensioned, preferably by a spring, in its engagement position.
The free end of the second lever arm in another embodiment of the present invention is bent or curved along the first pivoting direction, creating the engagement mechanism, especially the hook, whereby the face of the bent or curved free end that faces the first direction is provided with a hook nose with an engagement area that seizes the counterbearing and locks it. The lever can accordingly as a whole comprise a straight, curved or, depending on the situation, bent, at an essentially right angle for example, strip of sheet metal that terminates in a hook. If the end is straight, it can act as a first lever arm for example, with a point of engagement, a bore for example, for the first axis located therein. In this case, the other end, which can be bent for example, will act as a hook that hooks onto the counterbearing as the lever pivots in the first direction. It is on the other hand also conceivable for the first and second lever arm to bend toward each other, with a bore or similar bearing for the first axis located in the vicinity of the bend. The entire second lever arm will in this case comprise a hook with a nose at the end. A third lever arm can be provided in the form of a straight extension of the second lever arm, representing a point of contact for the unlocking component.
To allow the hook to hook onto or the nose to travel beyond the counterbearing that it is to engage behind even while it is being advanced during normal operation, it will also be preferable to provide the engagement mechanism with a snap-in nose and in particular for the hook nose or nose to be in the form of a snap-in nose. The side of the snap-in nose that faces the engagement area can be provided with an on-ramp shoulder. If the engagement mechanism is also provided with an obliquely angled capture area for seizing the counterbearing, the second lever arm will not be able to hook over the counterbearing subject to powerful force as might happen if a pointed capture area were to bore into the counterbearing. Tests have indicated that reliable locking can be attained even with an obliquely angled capture area.
It will be preferable to be able to fasten the counterbearing at various points along the track. The track can for example be a rail in the form of a length of C section, the counterbearing tensioned across it from one mutually facing edge to the other. An embodiment of the present invention is preferable wherein the counterbearing simultaneously constitutes or comprises a limiting mechanism that limits the closing motion of the carrier and accordingly prescribes its closing position. It will also be preferable for /27. the counterbearing to be constituted by one edge of the limiting mechanism and especially by an edge that extends into the C section.
The locking mechanism can be adapted to various sites even more easily if /28. the connecting rod is provided with several means of attaching it to any desired point on the door panel and of articulating it to any desired point on the first lever arm. This feature will be even more advantageous if it allows various distances between the door panel and the carrier to be spanned. T /29. he connecting rod in one concrete version is preferably flat and elongated and in particular a perforated strip of metal, whereby the means of attaching it to any desired point on the door panel and of articulating it to any desired point on the first lever arm are in the form of several preferably round holes distributed along it.